Photovoltaic devices can include semiconductor material deposited over a substrate, for example, with a first layer serving as a window layer and a second layer serving as an absorber layer. The semiconductor window layer can allow the penetration of solar radiation to the absorber layer, such as a cadmium telluride layer, which converts solar energy to electricity. Photovoltaic devices can also contain one or more transparent conductive oxide layers, which are also often conductors of electrical charge.
Processing of photovoltaic cells can include heat treatment of cadmium telluride coated plates with cadmium chloride, which can improve crystalline quality and transport properties in cadmium telluride. In conventional multi-step methods of cadmium chloride treatments, cadmium chloride is applied to a cadmium telluride coated plate in a first step by a technique such as solution spraying, dipping the plate into solution, vapor application, or atomized mist application. The cadmium chloride is then activated by heat treatment in a second step.
However, the various known multi-step methods include several drawbacks including a lack of control over humidity, which could facilitate formation of cadmium telluride-chlorates, and longer processing times due to the multi-step process. Accordingly, a simplified process for cadmium chloride treatment is desired.